I don’t particularly know much about this specific topic but, it would be trivial for them to read what’s seen in the app. The encrypted part is only during transfer of a message, your app is still decrypting it to plain texts, and meta can just read the message at that point.

Hm. I wonder if still will become a problem in the future if we get more Linux native games. We shit on Windows for not playing old games when wine can, but if a game stops functioning moving from x11 to Wayland (or some other dependency) will there be people there to care enough to fix it? Although I would assume it would be an easier fix for Linux than Windows for when it does.